Monday, May 2, 2011

Call it a Week....

This week we round up some various and largely unrelated items for your viewing pleasure. We actually had a number of interesting things planned, and NONE of them really panned out. It was one disaster after another. The result was there really wasn't much to show. Busted....

Thanks to Count Domagni, we did get the new website up and running. It is now hosted entirely on Amazon.com. I'm assured it is graphically more pleasing than my large photograph efforts. But it has not been without problems. And we continue to struggle to work with all browsers and all movie formats. HTML5 was not the panacea expected, and so it is two steps forward and three steps back. We will stay with it. Many thanks for the various problem reports and suggestions.

Recall we had installed a brake transducer in the Mini Cooper. I'm quite enamored of this device and will post the first page of the data sheet here. They are available on DigiKey and they have them in a variety of pressure ranges and a variety of port sizes.

What I like about this device is that it puts out a 0-5v variable output based on brake pedal pressure. Actually, it reacts to changes in brake LINE pressure and of course that is a result of brake pedal pressure of course. It allows you to provide an input to your controller for regenerative braking that is truly representative of your pedal effort, giving a fantastic sense of control of regenerative braking.

The Mini Cooper Clubman has a power assisted braking system. We did NOT want to use a vacuum pump to enable that, and of course we DID want to take advantage of regenerative braking available in our AC induction drive system.

Recall we had replaced our TIMS600 controller, which I blew up, with a Rinehart Motion Systems controller at some additional expense. I have to tell you that I very much LIKE this controller, and cannot at this point recommend its use for any purpose. This thing just isn't done. We're kind of on the beta team.

Their manual had described a 5k potentiometer brake input for regenerative braking. But when we received the controller, we were told that that had not actually been implemented yet. But they planned to.

We have had a number of problems with the Rinehart, most notably a distinct and upsetting "shudder" when you first start in motion. They allude to "driveline resonance" as being the problem. As we had no such "driveline resonance" with the TIMS600 with the same motor, and have not encountered this in two other cars with AC induction drives, I guess I'm a little unconvinced that "its the car's fault." They put an anti-shudder algorithm in which helps, but then IT causes the car to jerk a bit when you are NOT moving.

In any event, they finally implemented the 3 wire input for regen and put in some new variables to set min, max, and change the brake mode.

We had previously helped them develop a braking ramp function based on time. This would cause the brake to initially match the regen level of the accelerator when you're foot was off the throttle, and ramp up to a maximum regen variable you could set. You can also assign a time value to the process. We use about 3 seconds. And so when you step on the brake, the regen linearly increases over the course of 3 seconds. If you start to develop too much braking, simply lift your foot and stab it again to reset the ramp. This brake "pumping" exercise is slightly annoying, but actually works pretty well. It was a huge improvement on what they had, which had been MAXIMUM braking when you first stepped on the pedal and then linearly DECREASING as RPM came down. This made no sense at all and felt terrible.

We wired up the transducer to the new inputs. The results were mixed.

First, the brake transducer regen works and works very well. Much improved brake feel and we can of course tune it further by changing the maximum brake torque and the mapping of the brake pedal input. But it introduced NEW problems. Most notably, at some random point between 3500 and 5000 rpm, the controller shuts down completely. This happens both on acceleration and braking and we could find no pattern other than it occurs somewhere in that rpm range, and so more often in first gear than second.

The more alarming and thoroughly inexplicable problem is that if you put it in electric "reverse" and give it just a touch of throttle, the car BUCKS violently.

Unfortinately, the Rinehart guys were out this week working with a motorcycle racing team and didn't have time to fool with us. This is a bit perplexing as it appears we are fooling around with THEM and spending a lot of time troubleshooting obvious problems that should have already been taken care of. Note that all of these items are NOT precisely configuration that we have not done correctly. Mostly they have involved new software releases to fix the problem. So we're kind of on the beta time with Rinehart.

As I like the physical package, we don't really mind. But it sure busted my program this week when they winked out on me. It takes some time to get set up for these tests and when you are reporting the results and have everything set up to make changes quickly and report back, it is a little disconcerting to get dumped for a better offer. Oh well, we have three guys and they have about that and it is just the nature of this cottage level industry.

We understand they are also working with a guy who has done an implementation of the Remy motor with a case that makes it something you COULD use and solves the cooling issues with this motor. More on that later.

So we think the Rinehart is a comer, but it's not quite ready for prime time yet.

We decided to install the PowerOne Aurora solar inverter in the garage at the house. This is a 6kw unit we showed on an earlier show that has a wide DC input range of 120-530vdc and puts out standard 240vac split phase 60Hz just like your house.

Our garage is separate from the house, but on the same side of the meter. I actually have an AC disconnect switch and natural gas 10kw generator already installed. If we lose grid, the switch disconnects us from the grid, connects us to the generator, and starts the generator. In this way, if they are out working on the grid, we don't light them up.
This is how this has been done for twenty years and it works extremely well. The problem is the switch is $400.

The Aurora is a grid tie inverter, and will match phase with your existing grid input. Any power you make with solar or wind for example, will be used locally and in fact, if it makes more power than you are using, it will run your meter backwards - if you have a meter that the utility hasn't modified to NOT run backwards, meaning you pretty much have to be in a net metering state at this point.

We hooked up the Aurora in kind of a strange configuration. I was going to connect it with a conduit to an existing box in the garage. Matt noted that we could just put a heavy cord on it, and plug it IN to the receptacle, giving us the option of UNPLUGGING it quite easily. I bit on it.

We plugged a cord we were using on a heavy heater into the jack and carefully measured the distance to the connectors in the Aurora. Matt then cut the cable with a large set of thankfully insulated cable cutters.

Unfortunately, we still had the cable plugged IN to the wall. We lose more interns this way. We included a little bit of video illustrating this event in today's show. Don't try this at home.

We did hook up the Mini Cooper to the inverter, and in fact it DID make power. Quite well actually. It was a tad over 6kw and in comparing the voltage and current IN to what it was reporting as output, this is a VERY efficient inverter, and totally silent. Good equipment.

Unfortunately, it won't work by itself as a backup power unit. Apparently, along the way, the power companies have caused some UL codes to be implemented that REQUIRES grid power for this device to operate at all. If you lose grid power, it shuts down as well. This "anti-islanding feature is ostensibly to prevent putting power out on the grid endangering the utility workers that might be working on the system.

What it really does is prevent you from using your solar or wind to backup your grid connection. I guess it eliminates the need for the $400 switch, but I smell an untold story of conspiracy and greed.

I went through every single inverter manufacturer I could find, and found a curious thing. They ALL had implemented this, and are apparently required to.

What about OFF grid inverters. Curiously, there aren't many of them anymore. But there are a few. Outback still makes some. But curiously THEY are ALL limited to single phase 120vac. There are no 240vac off grid inverters I could find. Curiouser and curiouser.

So to generate a split phase 240vac 60hz waveform, we have to go to battery backup. Predictably enough, any small inexpensive versions of that are ALSO limited to 120vac single phase. You can't simply use two of them. There is of course a phase relationship between the two phases to achieve the 240vac.

So I went back on eBay and had to find a refurbished and probably obsolete UPS battery backup system. We'll have to use THAT to generate the 240vac 60hz so the Aurora will have something to synch to. All this so I can use one of the cars as a battery backup. Since I have a generator, I don't even need this. I just wanted to demonstrate how to use an electric car to backup your house easily, if not inexpensively. The 6kw Aurora is already about $4000.

If any of you know of a small inexpensive circuit to convert DC to 240vac split phase, I'd like to hear about it. It doesn't need to make any power at all - just present the waveforms at milliamperes of current really.

The device actually DOES accomplish what I actually DO need. We often have to discharge a car to a low battery level to set fuel gages etc. It's a shame to just dump off that energy with the heater and waste it. Now I can plug a car in, and use the discharge energy for something useful, like running my house, while I discharge. But using it as an emergency backup just won't work, without buying a battery backup UPS system, which is what we are wanting to create. Kind of a circular chase, and all entirely unnecessary. This "safety" system is useless, and I would encourage anyone doing any kind of alternate energy power system, be it generator, solar, battery, wind, or whatever, to STILL get an automatic AC disconnect switch in any event.

Basically, this switch is just a huge transfer relay. It uses grid power to close a relay connecting the grid to your house. If you lose grid power, the relay deenergizes, connecting you to your alternate system, and in the case of a generator, also starting the generator.

If you get grid power back, it closes the relay, connecting you back to the grid, and disconnecting your house from the alternate source. This always did work most excellently. The "anti-islanding" built into the individual components looks very suspicious to me.

Again, if you know of a little inverter, even to work off a 12v battery to make 240v split phase waveform, we would like to hear about it. Note that there ARE 240v inverters, but these are single phase for European applications - it is NOT a two phase inverter.

Jack,This may not be the best solution, but you could try using a 12v to 120v inverter and then use a 24 volt tranformer to get 24v AC. Then take two 12v tranformers with the secondaries wired in series and connect them to the 24 volts. Then wire the primaries in series and you should get split phase 220v. 110v on each primary.

If you could find a single tranformer 110v to 220v with a center tap on the 220 side that would be much simpler, but I could not find one on ebay.

The reason why most grid tied inverters shut down when they no longer sense grid power is for safety reasons, if the output was still active and the grid goes down, linemen trying to do maintenance on the "downed" lines know they have turned the power off there end, but your still pumping juice in the other end....

I'm don't believe the approach of using a small inverter to provide the larger inverter something to sync to is viable, without some modification. The problem is that the small inverter needs to be running first this means the small inverter is trying to power the house for a small amount of time before the large inverter switches in. It wont be able to do this and will either shutdown or blow it's fuse straight away. It may be possible if we have a separate breaker isolating these backup systems (the small and large inverters) from the house until the large inverter is synced up. Then close the backup system breaker, which connects the backup systems to the house.

It may even be possible to find a switch which isolates the house from the mains when the backup system is engaged; and isolates the backup system from the house when the house is connected to the mains. This would be a very good idea in order to make the system safe.

On the finding a small 240v 2 phase inverter problem, I think the best approach is similar to what David Seabury proposed. The way to do it is use a European type “12 volt DC to 240 AC single phase system” and put the output into a centre tapped 240 Volt “Autotransformer”. That will give you your 2 x 120 Volt phases.

Alright who said to make video's of the cars driving by over and over and over. :) Stick with drives across town. Might for fun put a camera at bumper level for a short fun run. I am down for a hall effect throttle when they are available. Nice piece of work. Guess I do ramble a bit. But that adaptor is just the best. More to come later. It's actually a Midget but it sure looks like the B model from a distance. Just got a nice parts Midget for making Black Midge better. Still needs a new top. Nice upgrade to 120 volts and that Elcon 3000 works perfect.

Hiabout the inverter. No problemo http://www.victronenergy.com/inverters-chargers/quattro/

they have done that fore yearsI have used somthing like this on my boat to switch from shore power to batteri for years I have a 12v to 220v inverter (not with the fine sinus but the simpler and cheaper squarewave thing)If you want to cut with power on do it fast heheh

I think I can wire this transformer up to convert 120vac to 240vac split phase.

We would use this to bring the 6kw inverter up, and then cut it on with a switch to power the house and system.

I already HAVE a grid disconnect switch for the entire house and garage. They have been readily available for decades and they work extremely well - you lose grid power and the relay de-energizes, disconnecting your entire system from the grid very positively and connecting it to the secondary system. When grid power comes back, this is reversed.

ok got you point about the solar inverterthe solarinverter is good for 100-500v dc inputand inverters only 12-48v for the mostI have been talking to a company about that, using car batteries for powering the grid and they have just unpaking a new produktand they will phone back tomorowwhat we love, off the shelf component'syoursFjord

Incidentally, the "anti-islanding" is not just to protect linemen from your power, but to keep the load of the whole neighborhood from draining your power source and potentially damaging your equipment (and possibly your neighbors appliances).

I've had about six of you try to explain to me what a good idea "anti-islanding is. Have you read the blog you are commenting on?

I installed the largest residential photovoltaic installation in the world at my home (at the time of course, many now larger) in 1999. There, as well as at my current place, I have a very excellent UL listed grid isolation swithc that is very positive in its action. Pretty much foolproof. Making all this absurd.

The real question is why I would want an inverter WITH anti-islanding. It's nearly enough useless in any backup scenario. It can only serve to augment power when you DO have grid power. My main interest in solar was ALWAYS backup. Selling power to hte utility company is likewise absurd. We get about 1.5cents per kwh for "avoided cost" in MIssouri I think.

Yeah, net metering is great. You reduce your electric bill. But if I had spent a wad on a photovoltaic system here in Missouri with this "new improved" equipment, and found out later that if the grid goes down I go down too - unless of course I want to add the super dooper battery scooper backup unit, I would be pretty upset. They're managing to turn a very positive thing into a racket it smells like to me.

Another one of your bloopers Jack! I should not be laughing because that live cable cutting can be lethal but I was laughing hard on that last part of that video. I actually watched it again and again jut for laughs. That might win in Americas funniest...

The UK started with a road tax to maintain our roads. Now it is a road fund licence and the revenue far outstrips the costs of our road infrastructure. I'm excluding the incredible amount of taxes on fuel too!

Not to get off the topic here, but we have huge EVENT happened May 4th in our Neighboring City, Delray Beach have opened first in the Palm Beach County 3 public charging stations, 100% financed by private individual!

It has been in the main stream media news too, I've documented it on my BLOG.http://www.google.com/search?q=1-ev.blogspot.com

Jack,I am installing a Masterflux Sierra AC unit in my 1999 Lithium Solectria Force. I remember that you also used a Masterflux AC unit and had to include a blocking diode in the HV feed. What problems did you experience that necessitated the use of the diode? Looking forward to cool air here in Florida!Regards,Larry

Hi Jack - I am very interested in your comments about the pressure transducer. You note that it is available in many pressure ranges but I note that the "burst pressure" is pretty high (5X) although the overload is only rated to 2X.

Not know what your brake line pressure is one could (say) choose a trandsucer that provides full 5v at only half pedal or similarly one that provides only 2.5v at full pedal depending on your choice.

Have you been able to determine what brake line pressures your vehicles actually exhibit or has this been a trial and error sort of implementation for you?

Trial and error. But with no errors. I don't know if it is luck or what. We used a 500 lb transducer on the Speedster. You can get it up to about 4.9v but you have to mash it pretty good. On the Mini Cooper, kind of a unique situation. These are vacuum assisted brakes and we have no vacuum. So they are operational but VERY stiff. So we went with a 250 lb transducer. It is almost perfect. Again, very firm pressure will give you 4.75v. No pressure about 0.50 volts. A bit oddly mapped, which we can fix in software. About half pedal pressure (which is hard to estimate actually) gives us about 1 volt and full pedal pressure gives us 4.75v. So it's a little skewed, but actually not a bad mapping for regenerative braking as is. Gives you very good light control on light pedal but full brake is always there.

The Masterflux was an interesting problem. The compressor worked well, if somewhat loudly initiallly, in the garage. As soon as we would go for a drive, we'd blow the 30 amp fuse in the compressor controller. Almost immediately - certainly within a few blocks.

If we did this several times, we would blow the controller.

Our system was 375volts, well within the ratings of the specific controller we had. Revolt, the distributor, just really had no idea. They had never used one above about 150v at the time. We were at a loss.

I think Markus Siegert first suggested the diode. It worked, kind of leading to an understanding of what happened. Immediately obvious, AFTER you know what's going on.

On acceleration we use a good bit of current for a 375v pack. Maybe 300 amperes. The pack sags to about 345v in extreme acceleration but 360 v even under light acceleration.

The controller has either four or six input capacitors. When you apply power to the controller, which we did with a Kilovac Contactor, these caps charge to your pack voltage. We had no real inrush issues nor did we precharge this circuit.

Once we went on a drive, any reasonably strong acceleration lead to the pack voltage drop almost immediately. Incredibly, these little capacitors tried to power my car (kind of brings a tear) by discharging into the system. They do so with such enthusiasm, that they blow the fuse running current BACKWARDS through it in a vain attempt to hold that pack up at 375.

We put a 50 amp blocking diode on it that was certainly overkill. But it works beautifully. It simply stops this "backflush" from the controller back into the system.

Compressor works great now, and seems to be getting quieter as we use it. Still a little noisy.

The thing I like about this system is that you can replace their little pot and switch with a good quality pot and knob. The unit has such a wide range of operation, you can easily "tune" it to almost any air conditioning system to get just the right amount of "compressor" in the mix. We kind of do this by feel and not at all scientifically, but I still like the feature.

At this point my views on taxation have varied somewhat dramatically from my usual Libertarian approach.

I know none have the courage to even speak of it in our government, but at this point I favor a $5 per gallon federal tax on gasoline and diesel fuel.

I am concerned that we are going to go through progressive "waves" of this march on gasoline prices and that it has the potential to totally wreck our economy. We're actually pretty good at adjusting to things, but it takes time. I'd like them to declare a gasoline price emergency NOW, to avoid the future collapse, and counterintuitively, I want them to apply a $5 surcharge on the price of gasoline to avoid it.

Now if that isn't crazy, it is certainly out of the box. But let's think about it a minute. Let's say we ANNOUNCED a $5 gallon tax, but we implemented it at 25 cents per year. Each year, on a precise date, it bumps 25 cents. And it does this for 20 years.

Now what's the sense of THAT. It fosters investment in alternatives. From enactment, it lets everybody KNOW that gasoline is going to $10 per gallon at some point in the future. That allows an economic basis for investment in solutions. But by implementing it gradually, we induce a very reduced "shock value" to the concept. And so hopefully fails to trigger an economic collapse.

Gasoline prices are not inelastic. A quarter will reduce consumption to some degree. Another quarter a little bit more. So this reduction in use should have some amelioritive effect on gasoline prices ironically. And increasingly so as the tax graduates to higher levels.

But what we're after here is the shock value of a $5 gallon tax, and the impact of a 25cent tax. It would be the FIRST serious attack on the energy problem that we've been giving lip service to since Richard M. Nixon. It would be an incredibly powerful message to the oil producing nations, including "nations" such as Exxon, BP, etc.

But it would be an enormously powerful message to everybody. Your gasoline IS going to go up in price. But nobody knows when, if, or where. With such a tax, everybody knows your gasoline is going to go up in price, and whether it does or not it's going to go up $5 anyway.

Americans would find the concept of $9 or $10 gasoline shocking. But they have 20 years to get used to the concept, and a lot of minds out there would see opportunity in the disaster. More and better, they have TIME to develop those ideas, investment capital would be readily available for such ideas, and the vast gears of American ingenuity would come into play in a directed fashion.

Obviously it would generate a lot of revenue. It would be inflationary, but somewhat gradually so.

The main attraction is the mental shock value rather precedes the reality by a 20 year time frame. A side effect is it rather enhances our financial situation as a nation with a lot of debt.

In fact, I personally believe it would have an incredible unintended consequence in the first few years. The unholy alliance of a stronger dollar with a modestly decreased demand for gasoline and a kind of overnight change in the power structure of who's doing what to who over oil, I would predict that for the first three years, the tax would be free. The price of gasoline would decrease faster than the actual tax would engage. It would be therefore initially invisible.

The underlying dynamics of oil production and consumption unfortunately do not actually change. In further years, that and the tax start to regressively increase the cost of personal mobility. But that provides several years of time to arrange your living quarters closer to work, develop your bicycling skills, and yes, develop a taste for electric car usage for at least a portion of your personal mobility.

It's kind of a stick in the sand declaring war on the oil problem. ANd that certainty gives a bit of an investable opportunity for alternatives.

What has held us captive to a hundred year old technology is not that the price of gas has been too high, the problem is it has been too low and somewhat artificially so. We are essentially borrowing money to make gasoline affordable for the masses.

With the NFL and baseball, we have basically reinvented the essential and crucial components of a true democratic republic, bread and circuses.

Hey Jack,you said "Americans would find the concept of $9 or $10 gasoline shocking. But they have 20 years to get used to the concept,"

Ha,today Europe already have that price of $8-10 a gallon ($2 and more a liter) and they dealing with it. They have to be The First in line on gas increase, so US have some time to "see" what happened...

They are more interesting in EVs, I've heard French Post Service are ordering lot of EVs...